Cost-Effective, Hydrogen-Rich, and Ultramicroporous Metal–Organic Framework for Efficient Separation of SF<sub>6</sub> from N<sub>2</sub>
Mingshan Yang, Zhuoyan Wan, Pengtao Guo, Miao Chang, Gan Li, Huifang Li, Dahuan Liu
Abstract
It is essential for the industry to create an adsorbent that combines a high capacity with selectivity to achieve the effective separation of SF 6 from gas mixtures. In this study, we prepared a cost-effective nickel-based metal–organic framework (MOF), Ni(BTC)(BPY), which features hydrogen-rich ultramicroporous channels specifically designed for separating SF 6 /N 2 gas mixtures. The findings from the adsorption experiments demonstrated that Ni(BTC)(BPY) achieved a remarkable SF 6 adsorption capacity of 5.08 mmol g –1 and an ideal adsorbed solution theory SF 6 /N 2 selectivity of 382. This effectively resolves the trade-off encountered in the development of adsorbents between capacity and selectivity. Theoretical calculations indicated the optimal adsorption sites for SF 6 within the pore channels. The strong interactions between the F atoms in SF 6 and the numerous H atoms in the channels account for the superior SF 6 adsorption performance of this material. Breakthrough experiments provided additional evidence that the MOF can completely separate SF 6 /N 2 mixtures, positioning it as an excellent candidate for recovering SF 6 from these gas mixtures.